Please Help -- Do While Loop continues disregarding boolean statement

Hi, I am a beginner in programming and for this assignment (for an online class) I cannot seem to figure out how to fix/what I am doing wrong and since its an online class I really cant ask for help.Please help! So in my code I would like the user to enter a scale either 'c' or 'f'....now if you enter anything else it catches the error but then still proceeds! also, when rounding the calculated conversion...i am not getting a rounded answer only **.00 the asterisks being any numeral. here is my code: